I never used ICQ. I found it cumbersome on my older rigs. I didn't know many people who used it. However, I was hooked on AOL IM once I found out I didn't need AOL to chat with my AOL subscribed buddies.
I got so many people to use it too. I showed them how clean and solid AIM was (and back in the late 90's, it was THE most STABLE IM client available...
But once they upgraded their interface, one that was a resource HOG and contained obtrusive advertisements... I stopped using it.
When I found Google Chat (now Google Talk) I switched immediately. I tried to get people to switch, once they had Gmail accounts of their own, but people were set in their ways. It was AIM, or Yahoo! chat or nothing. Yahoo! chat I noticed had quite a following, one that I missed out on, but I only used it for school projects where I needed to work on the whiteboard remotely.
However, once Facebook became ubiquitous, all bets were off. People switched en masse to Facebook Messenger, despite how horrible it was, and apparently, still is.
I am glad that, for the most part, Google Talk still works with AIM. However, since Facebook Newsfeed (and the introduction of non-college students) to Facebook, I have reduced my usage drastically. I now no longer even have Facebook active on my new Android Phone. When I had Blackberry, I actually had a short resurgence, as BB is the only OS to fully integrate their FB client with the rest of their software. But in the end, I don't want to be given important invitations and communication via FB. I don't want chats from my FB friends. It is there if I need it.
Unlimited SMS texting from my no-contract Virgin Mobile phone... That is my main communication now. It is fairly reliable, instant, and doesn't crash my phone/computer.